Which statement is correct?
a) parasympathetic preganglionic fibers are short.
b) sympathetic fibers originate in the brain and sacral spinal cord.
c) parasympathetic ganglia lie close to the spinal cord.
d) sympathetic ganglia lie close to the spinal cord.

The correct answer is option D) Sympathetic ganglia lie close to the spinal cord.

Explanation:

Our body has an autonomous nervous system (ANS) responsible for regulating and unconsciously controlling our internal organs. Within the ANS, there are the nerve fibers that connect the central nervous system with the ganglia. These fibers are called preganglionic fibers. A synapse crossing must occur in the first instance from a preganglionic to a postganglionic neuron before nerve stimuli are transmitted to any of the organs.

All preganglionic fibers use a molecule called acetylcholine as a neurotransmitter and target the ganglion. They can be sympathetic or parasympathetic preganglionic fibers.

The difference between them is that sympathetic preganglionic fibers are shorter than parasympathetic preganglionic fibers because sympathetic ganglia are closer to the spinal cord.

Also, parasympathetic preganglionic fibers usually have differences in their divergence factors with sympathetic preganglionic fibers because of the number of synapses formed by sympathetic preganglionic fibers with ganglion neurons.

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explanation: